, have been shown in galleries across europe and asia with the man on the lecture circuit to explain how they work. >> a backbone which makes a circular movement like this. >> reporter: is this engaging mixture of engineering and whimsy really art? yes, it is says the head of sculpture at london's royal college of art. what is it that draws us in? >> i think audiences like to experience wonder before things. this is an encounter of wonder and awe. >> reporter: wonder, awe, and sheer enchantment. the beasts are irresistible to passers-by. and passing dogs. the secret of their uncanny life-like walk, he says, is the proportion of the leg parts which he worked out as a computer algorithm. >> one of the major criteria was that a leg shouldn't spend too much time in the air. just go back to the ground. we have to think of real animals trying to seek balance. >> reporter: he is hoping for a major exhibit in the u.s. next year. his only worry? that the manufacturer will stop making his raw material. >> this is enough for the rest of my life. >> reporter: is it really? for the rest of your life?